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    <title>inv_coeff</title>
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    <center>Scilab Function</center>
    <div align="right">Last update : April 1993</div>
    <p>
      <b>inv_coeff</b> -  build a polynomial matrix from its coefficients</p>
    <h3>
      <font color="blue">Calling Sequence</font>
    </h3>
    <dl>
      <dd>
        <tt>[P]=inv_coeff(C,[,d,[name])  </tt>
      </dd>
    </dl>
    <h3>
      <font color="blue">Parameters</font>
    </h3>
    <ul>
      <li>
        <tt>
          <b>C</b>
        </tt>: big matrix of the coefficients</li>
      <li>
        <tt>
          <b>d</b>
        </tt>: Polynomial matrix degree. optional parameter with default value  <tt>
          <b>d=-1+size(C,'c')/size(C,'r')</b>
        </tt>
      </li>
      <li>
        <tt>
          <b>name</b>
        </tt>: string giving the polynomial variable name (default value <tt>
          <b>'x'</b>
        </tt>).</li>
    </ul>
    <h3>
      <font color="blue">Description</font>
    </h3>
    <p>
      <tt>
        <b>P=inv_coeff(Mp,k)</b>
      </tt>, when <tt>
        <b>k</b>
      </tt> is compatible with <tt>
        <b>Mp</b>
      </tt>  
    size, returns a polynomial matrix of degree k. <tt>
        <b>C=[C0,C1,...,Ck]</b>
      </tt> and 
    <tt>
        <b>P= C0 + C1*x +... +Ck*x^k</b>
      </tt>.</p>
    <h3>
      <font color="blue">Examples</font>
    </h3>
    <pre>

A=int(10*rand(2,6))
// Building a degree 1 polynomial matrix
P=inv_coeff(A,1)
norm(coeff(P)-A)
// Using default value for degree
P1=inv_coeff(A)
norm(coeff(P1)-A)
 
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    <h3>
      <font color="blue">See Also</font>
    </h3>
    <p>
      <a href="poly.htm">
        <tt>
          <b>poly</b>
        </tt>
      </a>,&nbsp;&nbsp;<a href="../polynomials/degree.htm">
        <tt>
          <b>degree</b>
        </tt>
      </a>,&nbsp;&nbsp;<a href="../polynomials/coeff.htm">
        <tt>
          <b>coeff</b>
        </tt>
      </a>,&nbsp;&nbsp;</p>
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